🎨 Palette: Add native keyboard click sounds to accessory bar buttons

[emkey1]

💡 What: Added standard iOS keyboard click sounds to the custom terminal keyboard accessory buttons.
🎯 Why: Previously, tapping the custom keys (like Esc, Ctrl, Arrow keys) in the terminal was completely silent, breaking the expected native iOS typing experience and leaving the user without auditory feedback.
📸 Before/After: Silent button taps -> Native keyboard click sound.
♿ Accessibility: Provides important auditory confirmation for non-visual interactions.

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PR created automatically by Jules for task 3252043204413605434 started by @emkey1

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